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1.
The cortical development and macronuclear evolution of the marine hypotrichous ciliate Anteholosticha manca, collected from the coastal waters near Qingdao, China, were investigated using the protargol impregnation method. The morphogenesis of A. manca is generally typical for the genus, and can be characterized as the following features : ( 1 ) in the proter, a new oral primordium is formed on the bottom (beneath the pellicle) of the buccal cavity, disorganization of the parental undulating membranes do not contribute to the formation of this primordium ; (2) FVT-cirral anlagen in both dividers develop independently, and very likely only a few midventral cirri join in the formation of these primordia; ( 3 ) both marginal row and dorsal kinety anlagen develop intrakinetally within the parental structure; (4) at the middle stage, macronuclear segments fuse together to form a single mass as observed in most of its related forms.  相似文献   

2.
The soluble organic matters were extracted from marine sediments in the sea area of Southern Ocean by using organic solvents. The hydrocarbon and carboxylic acid fractions were separated with the thin layer chromatography. The organic compounds of 170(H), 21α(H)- bishomomoretene, cholest - 5 - ene, 24 - methyl - cholestene, 24 - ethylcholestene, hop-17(21)-ene, neohop - 13(18)-ene, fern-8-ene, fern-7-ene, 170(H), 210 (H) - hop - 22(29)-ene (diplotene), steranes, β, β-hopanes C29 -C31 and unsaturated carboxylic acids C18:2Δ9.12 , C18:1Δ9,C18:1Δ11 , have been identi-fied in the hydrocarbon and carboxylic acid fractions by means of gas chromatography and gas chromatography - mass spec-trometry - data system. The distributions of 3, a - bishomomoretene, β,β- hopene and β,β- hopane are characteristic of immature organic matter. The sterane, C29 20S/20R epimer ratio 0. 6 indicate that the organic matter had experienced a thermal evolution in the early sedimentation. The unsaturated fatty acids espec  相似文献   

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